When Florida Gov. Rick Scott endorsed the Medicaid expansion last month, it was a huge turnaround: He had initially been one of the health law's harshest critics.

While that was a major moment for the Affordable Care Act, it did not secure the Sunshine State's participation in a Medicaid expansion expected to cover 1.3 million Americans.

One less-noticed factor in Florida — or in any other state — is that it's not just the governor who has to get on board with expanding Medicaid. The state legislature generally has to sign off on the program and authorize the new spending it would entail.

In Florida, WFSU's Lynn Hatter reports, the Republican-controlled Florida House of Representatives has signaled it "won't go along" with the governor's Medicaid plans:

 In a meeting [Monday], the House’s Select Committee on the Patient Protection and Affordable Care Act said the state can’t rely on promises from the federal government that it might be unable to keep.

“What the federal government gives, it can take away,” said state Rep. Kathleen Passidomo, R-Naples.

The vote against the Medicaid expansion was along party lines, with 10 Republicans voting no and five Democrats voting in favor of the expansion.

In other words: The legislation necessary to expand Medicaid in Florida failed to make it out of the House committee. The Senate is set to vote on the same legislation later Tuesday, Hatter reports. It's also controlled by Republicans, but has shown more openness to the health-law program.

This challenge likely isn't unique to Florida: In Ohio, Gov. John Kasich needs his Republican legislature to sign off on a Medicaid expansion, as does Gov. Rick Snyder in Michigan. New Jersey Gov. Chris Christie is likely to have an easier time there, as his state legislature is under Democratic control.

Convincing Republican governors to endorse a major pillar of a controversial law is no small feat for Obamacare advocates. But it does not ensure that states will move forward — that likely takes convincing a wide swath of local legislators who already stand in staunch opposition.